The present invention relates to a method and apparatus for removing skins and pits from avocados and the like and more particularly to such a method and apparatus wherein the avocados are initially subjected to thermal treatment for loosening their skins.
Avocados are similar to other foods including fruits and vegetables such as tomatoes and peaches, at least to the extent that their skins are commonly removed before conversion to a processed food product. However, the processing of avocados to separate their usable flesh from the avocado skin and pit has not developed at the same pace as other foods. This has been due in part to the thermal sensitivity of the avocado flesh and its relatively limited shelf life, particularly in a ripened condition. At the same time, it has been found to be quite difficult to process ripened avocados because they are quite fragile.
In a copending U.S. patent application, Ser. No. 628,920, entitled METHOD FOR REMOVING SKINS FROM AVOCADOS, filed on July 9, 1984, now abandoned in favor of Continution-in-part application Ser. No. 778,845, filed Sept. 23, 1985, which issued as U.S. Pat. No. 4,600,593, dated 7/15/86, a method was disclosed for loosening the skins from avocados by thermal treatment. As disclosed therein, the avocados are preferably immersed in a hot triglyceride oil such as avocado oil or the like in order to loosen the skins from the avocado flesh without causing thermal degradation of the avocado flesh.
The method set forth by this reference to initially loosening the skins of avocados is contemplated for preferable use prior to the method and apparatus of the present invention. However, it is to be understood that the method and apparatus of the present invention could be employed with avocados or similar products for removing the skins and pits without the thermal treatment step of the reference. For example, if the avocados were sufficiently ripened so that their skins were relatively loose, the method and apparatus of the present invention could be employed without prior thermal treatment to loosen the skin.
In any event, because of the high nutritive value and unusual composition of the avocado fruit, it has special value as a food product. However, in view of its relatively fragile nature and short shelf life, for example, the avocado is most useful in a fresh or fresh frozen form. Because of the expense and difficulty in separating the avocado flesh from the skin and pit in the past, the level of use of avocados in various food products has heretofore been relatively limited. It is believed that market demand would be substantially greater if the avocado flesh were readily available for further processing or combination in food products.
In the past, the skins of avocados and like products have often been removed manually, not only resulting in an expensive and time-consuming operation, but also being characterized by the loss of part of the desirable green chlorophyll layer lying just beneath the avocado skin.
Mechanized techniques for separating the avocado flesh from the skin and pit have been developed in the past but only with accompanying limitations. For example, one such technique involved halving of the avocado fruit and removal of the pit, the resulting avocado halves being pressed between two surfaces to extrude the flesh through perforations in one of the surfaces. Although this process overcame the expense of manual operations, it necessarily resulted in the recovered avocado flesh being extruded or mashed. By contrast, it is desirable in certain food products that the avocado be present in various textures and it is therefore desirable to separate the avocado flesh in relatively integral portions.
In any event, there has been found to remain a need for an improved method and apparatus for the processing of avocados in order to effectively separate the avocado flesh from its skin and pit. In carrying out such a process, it is also necessary to allow for the relatively fragile nature and unique characteristics of avocados and the like.